\chapter{\LaTeX123} 
\begin{intro}
  This is the \LaTeX123 for the \index{beginers}beginers,you may try the exmaples when you learning it.
\end{intro}
\section{a short exmaple}
\subsection{about the table}
\begin{table}[htbp]
\caption{example}
%\vspace{1.5}
\centering
\begin{tabular}{lll}
	\hline
	be happy! & aaa & bbb \\
	\hline
	so be happy & ccc & ddd\\
	\hline
\end{tabular}
\end{table}

\begin{verbatim}
\documentclass{report}%the source code;
\end{verbatim}

\begin{figure}[htbp]
 \centering
 \begin{minipage}[t]{0.4\textwidth}
     \centering
     \includegraphics[scale=0.1]{../fig/linux}
     \caption{left}
 \end{minipage}
\begin{minipage}[t]{0.4\textwidth}
    \centering
    \includegraphics[scale=0.1]{../fig/vi}
    \caption{right}
\end{minipage}
\end{figure}
%Form figure~\ref{fig:legt}
\pagebreak
\begin{itemize}
  \item{great books}
  \item{\url{http://www.bupt.edu.cn/}}
  \item[-]{classic films}
    \begin{itemize}
      \item{Pressure changes everything, some people you squeeze them, they focus, others fold.}
    \end{itemize}
  \item[*]{fantestic music}
\end{itemize}
\section{Notes of summer}
\subsection{Rabbit}
Take care of the programing style,refer to kenos.\\
Don't make the grammer mistakes.\\
\subsection{C function}
This is for the time and date functions.\index{first!functions}The related functions :time, asctime, gmtime, localtime. To use the time and date functions we have to include the head file <ctime> or <time.h>.
\begin{enumerate}
  \item{asctime}~char *asctime(const struct tm *timeptr)

  \item{ctime}~ char *ctime(const time\_t *timep)  将时间和日期以字符串的形式返回
    \begin{verbatim}
    time_t timep;
    time(&timep);
    cout<<ctime(&timep)<<endl;
    return 0;
    \end{verbatim}
  \item{time}~time\_t time(time\_t *t) get the time now此函数将返回从公元1970年1月1日的UTC时间，从0时0分0秒起到现在所经过的时间（秒数）
    \begin{verbatim}
    int seconds = time((time_t*)(NULL));
    cout<<seconds<<endl;
    \end{verbatim}
\end{enumerate}
\subsection{Dynamic memory allocation}
\begin{itemize}
  \item one dimension~ eg:char *p = new char[n]
  \item two dimension~eg: pp[n][m]
  \begin{verbatim}
  char **pp = new char *[n];
  for(int i = 0; i < m; i++)
  {
  		pp[i] = new char [m];
  }
  
  \end{verbatim} 
\end{itemize}
\subsection{Class Objects}
when define a class, we are defining a type. Once a class is defined, we can define objects of that type. Storage is allocated when we define objects, but(ordinarily) not when we define types:define a new type, but does not allocate any storage. When we define an objects, the complier allocates an area of storage suffcient to contain a defining type object. Each object has its own copy of the class data members.Modifying the data members of one object does not change the other's.
\subsection{Compile Linux Kernel}
\verbatiminput{../code/building_linux_kernel}
\subsubsection{ Mount an image}
Linux loop-back\\
\begin{verbatim}
 # mount -t iso9660 -o loop file.iso /mnt # Mount a CD image
 # mount -t ext3 -o loop file.img /mnt    # Mount an image with ext3 fs
\end{verbatim}
\subsection{Interface}
事情往往是这样，只有在你构造和使用了程序的第一个版本之后，才能对如何把系统设计正确有足够的认识。
\par 先做出一个将要丢掉的，做出一个原型，我们的第一个版本将忽略许多完备的工程应该设计的难点，但却又必须足够完整和有用，以便帮助我们熟悉问题。

